Blade grinder



Feb. 17, 1970 m E'fAL 3,495,361

BLADE GRINDER Filed Aug. 2. 1967 2 Sheets-Sheet 1 Fig- Alfred m,

Frank A. Geber/ 1N VENTORS Feb. 17, 1970 KLE|N ET AL I 3,495,361

BLADE GRINDER 4 A, (I 2 2 4 III w .M s s i 2 0 6 4 0 M h R 0 m m 4 5 w 6 M /Z m M S H 0 m "m a .V I m llllll m W w m Ya I (/6 0 r a. m m 6 \r a An 2 I! II WW m 4 1 8 m v 8 8 4 m T1 n 4 8 F 4 w o 4 m 8 6 8\ M 4 5 5 Filed Aug. 2. 1967 Fig. 3 I 34 United States Patent U.S. Cl. 51249 Claims ABSTRACT OF THE DISCLOSURE A power driven hand held grinder mountable directly on and movable along a doctor blade. The device includes a housing which is received over the doctor blade and guided directly on the blade holder, the housing in turn adjustably mounting the power driven grinding wheel.

The instant invention is generally concerned with blade grinders, and more particularly relates to a unique power driven hand manipulated device specifically adapted for grinding doctor blades.

The doctor blade, which we are herein primarily concerned with, is used in all forms of gravure printing, be it for textiles, paper, plastics or any other media. Gravure printing, by its very nature, requires the use of a sharp, knife-like blade, commonly referred to as a doctor blade. This blade is utilized in scraping the excess color off the printing cylinder or plate, and as such, must be filed or ground perfectly straight and parallel to the blade holders or shears which hold the blade into the printing machine. Besides being ground perfectly straight, a specific angle must be provided or ground on the edge of the doctor blade so as to enable it to give a smooth and even wipe of the roller, thereby preventing any unwanted color from applying onto the object which is to be printed.

Until recently, the doctor blades have been hand filed, this being a time consuming, unsafe and somewhat costly operation. Aside from this, by hand filing it is almost impossible to insure a straight edge, and as a result printers are forced to run the blades at greater pressure against the rollers, this in turn resulting in excessive wear both on the blade and on the rollers. Recently, various doctor blade grinding machines have been devised. However, such machines are expensive stationary units which require the blades to be brought to the machine. On the contrary, the doctor blade grinder of the instant invention is a small portable unit, weighing between 8 and 10 pounds depending upon whether air or electric drive is provided, which can be easily moved from place to place and is thereby usable by any printer right at the site of his printing machine. Further, the blade grinder of the instant invention actually engages and is guided by the doctor blade holder or shear itself, and by this means assures a grinding of the blade edge parallel thereto.

Accordingly, the instant invention eliminates the expense, danger and uncertainty of hand filing, and does so without requiring the installation of expensive stationary machinery to which the doctor blade must be brought. This is effected through the utilization of a unique portable unit which can be brought directly to the printing machine and quickly engaged with the doctor blade for guided movement thcrealong.

Another significant object of the instant invention resides in the incorporation of means for grinding the blade at any one of a plurality of angles as might be desired.

Likewise, it is significant that the grinding apparatus of the instant invention is adaptable for use with either air or electric power, the apparatus consisting primarily of a unit which is capable of reception over a doctor blade and guided engagement with the blade holder or shear, and

3,495,36l Patented Feb. 17, 1970 which is also capable of adjustably mounting a power dcriiven grinding wheel for engagement with the blade e ge.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view of the blade grinding device of the instant invention mounted in operative position on a doctor blade;

FIGURE 2 is a perspective view of the rear portion of the device;

FIGURE 3 is a front elevational View of the device;

FIGURE 4 is a side elevational view of the device;

FIGURE 5 is a cross-sectional view taken substantially on a plane passing along line 55 in FIGURE 3;

FIGURE 6 is a cross-sectional view taken substantially on a plane passing along line 66 in FIGURE 3; and

FIGURE 7 is a sectional detail taken substantially on a plane passing along line 77 in FIGURE 4.

Referring now more specifically to the drawings, reference numeral 10 is used to designate the blade grinding device or apparatus comprising the instant invention. This device, as illustrated in the drawings, is particularly adapted for use in grinding a doctor blade 12, or more particularly the angularly orientated straight upper edge 14 thereof. In performing this function, the device 10 engages on and is guided along the front holder or shear 16 which is in the nature of an elongated bar, the guiding of the device 10 along the holder 16 insuring a parallel relationship between the edges 14 being ground and the holder 16.

Basically, the device 10 is utilized to mount and properly orientate a power motor 18 which may be said to actually constitute a portion of the devices or apparatus 10. This power motor 18, either air or electric, is releasably and adjustably mounted within a motor mounting unit 20 which is in turn adjustably mounted within a housing 22.

The housing 22 includes a pair of parallel laterally spaced fiat side walls 24 and a rear wall 26 interconnected between the rear edges of the side walls 24 so as to define in effect a three-sided housing. The top of the housing 22 is to be selectively closed by a transparent plastic safety plate or shield 28 slidably supported within opposed channels or grooves 30 and 32, the groove 30 being defined along the inner face of the back wall 26 adjacent the upper edge thereof, and the groove 32 being defined along the inner face of a relatively narrow channel bar 34 engaged between the side walls 24 adjacent the upper portion of the front edges thereof. As will be appreciated from FIG- URE 2, the top panel 28 can be slid completely from the housing 22 beyond one of the side wall 24, this particular side wall 24 having the upper edge thereof downwardly offset sufficiently so as to allow for a free movement of the panel 28 thereover into and out of the opposed channels or tracks 30 and 32. Manipulation of this transparent facing panel 28 is effected through an elongated upwardly projecting fingergrip 36 having a lateral flange afiixed directly to the panel 28 adjacent the outer end thereof.

It is also contemplated that a front transparent plastic safety panel 38 be provided. This front panel 38 is slidably received within inwardly directed opposed vertical channels or tracks 40 defined in the opposed side walls 24 parallel to and immediately adjacent the front edges thereof. From the drawings, it will be noted that the upper transverse front bar 34 is actually offset inwardly of the extreme forward edges of the side walls 24 so as to allow room for the provision of the opposed tracks 40. The front panel 38 will of course be vertically slidable,

and limited in its operable position by engagement with the motor mounting unit 20 or an appropriate stop provided slightly thereabove. Further, a complete removal of the front transparent safety panel 38 will be effected through an upward movement thereof out of the opposed channels or tracks 40.

The doctor blade 12 itself, during the actual grinding operation, is received vertically within the housing 22 through a pair of downwardly opening vertically elongated slots 42 provided in the opposed side walls 24 generally centrally between the front and rear vertical edges thereof. The bottom edge of each side wall 24, rearward of the corresponding vertical slot 42 therein, is provided with a laterally extending flange 44 having a front to rear elongated bolt slot 46. An elongated stabilizing and positioning bar 48 extends across the housing immediately below the flanges 44 and coplanar lower edge of the back or rear wall 26 and is fixedly bolted, by suitable bolt and nut means 50, to the two flanges 44 for selective locking in a plurality of transversely adjusted positions. The actual bolt and nut means can, if so desired, comprise in each instance a threaded shaft welded to the upper surface of the stabilizing bar 48 and projecting vertically through the elongated corresponding flange slot 46, and a nut threaded thereon and in direct engagement with the upper surface of the flange 44. In this manner, upon loosening of the nuts, the bar 48 can be shifted forwardly so as to engage the forwardly directed bevel produced thin edge 52 thereof against the rear face of the doctor blade 12, thereby firmly although slidably positioned the doctor blade 12 against the front edges of the two opposed blade receiving slots 42. Thus, a consistent positioning of the doctor blades will be assured, while at the same time providing for slight variations in different thickness of the blades. Furthermore, the thin engaging edge 52 of the bar 48 allows for a free sliding movement of the device along the doctor blade 12 during the grinding operation.

Immediately forward of the doctor blade receiving vertical slots 42, the bottom edge of each of the side walls 24 is provided with a downwardly directly right angular notch 54 which combine to seat a downwardly and rearwardly inclined mounting plate 56 preferably Welded or otherwise permanently affixed to the side walls 24. Noting FIGURES 4 and in particular, it will be seen that each of the side walls 24 actually includes an integral depending portion 58 immediately rearward of the corresponding notch which acts in the manner of a back-up for the angnlarly depending mounting plate '56, this projection 58, on each side wall 24, having a forward edge continuing the inclination of the slot 54 against which the plate 56 seats, and rear edge forming an aligned continuation of the forward edge of the blade receiving slot 42.

An elongated guide bar 60 in turn overlies the forward face of the mounting bar 56 and projects, along the full length thereof, below the lower edge of the mounting bar 56 at the same angle for engagement with the straight flat upper edge 62 of the front holder bar 16. At the same time, it will be noted that the engaging lower edge portion of the guide bar 60 includes, in addition to the horizontal face 64 which engages the holder 62, a vertical face 66 which engages directly against the front face of the doctor blade 12. Finally, an angular stabilizing member 68 overlies the forward face of the guide bar 60 with this member 68 including a first leg 70 positioned against the front face of the bar 60 and a second leg 72 extending at right angles from the lower edge of the first leg 70 for stabilizing and guiding engagement with a downwardly and forwardly angled continuous face 74 also provided on the holder bar 16 immediately below the horizontal top edge 62 thereof. This particular construction and its relationship to the holder bar 16 will be best appreciated from FIGURE 5. It is contemplated that at least the stabilizing member 68 be adjustable, and

as such, the upper mounting leg 70 thereof is to be provided with a pair of transversely elongated bolt receiving slots 76 through which the two headed mounting bolts 78 project. These bolts 78, in addition to mounting the member 68, can also be utilized in mounting the guide bar 60 on the base or mounting bar 56 which, in order to accommodate the threaded inner end portions of the bolts 78, can be provided with internally threaded bores therein, or can, as an alternative, be provided with smooth bores through which the bolts 78 will pass for engagement with nut means fitted against the rear surface of the mounting plate 56. Further, if so desired, the guide bar 60 can also be provided with vertically elongated slots similar to the slots 76 so as to enable an adjustment of the bar 60 along with or relative to the member 68.

In the structure thus far described, it will be appreciated that there is a positive engagement with both faces of the doctor blade, as well as two faces of the holder bar, thereby achieving a stable relationship between the device 10 and the doctor blade for movement of the device along the doctor blade when grinding the upper edge 14 thereof parallel to the holder bar 16, as shall be described in more detail subsequently.

Referring now particularly to the motor mounting unit 20, it will be noted that such includes a pair of opposed side plates 80 and a transverse front plate 82, thereby defining in effect a U-shaped body. The front plate 82 has a circular power motor opening 84 defined centrally therethrough for the snug reception of the main body of the motor 18 therein in a manner so as to position the subsequently mounted grinding wheel 86 inward thereof as will be best appreciated from FIGURES 1 and 2. The front plate 82 includes a central slit 28 extending radially outward from the circular motor receiving opening 84 through the top edge of the plate 82 whereby a selective movement of the upper side portions of the front plate 82 toward and away from each other can be effected so as to provide a positive clamping of the power motor 18 within the motor receiving opening '84. This actual movement of the upper portions of the front plate 82 is effected by means of a clamping screw 90 received transversely through the upper portions of the plate 82 and across the intervening slot 88, noting FIGURE 3 in particular. This clamping screw 90 includes a threaded shank portion which extends through a smooth bore 92 in the first plate portion and is threadedly received within an internally threaded bore 94 in the far or second plate portion. In addition, an enlargement or shoulder 96 is provided for bearing engagement against the side edge of the first portion whereby a rotation of the screw 90, through the laterally bent handle portion 98, will result in a selective slight movement of the upper plate portions toward or away from each other. As will be readily appreciated, in light of the relatively snug fit of the power motor 18 within the plate opening 84, this movement, achieved through the inherent slight degree of resiliency presented by the presence of the slot 88, need only be very slight in order to effect a proper clamping of the motor 18.

Rigidly aflixed to the outer surface of one of the side plates 80 is a relatively thin cylindrical disk 100 which is in turn rotatably affixed, through an axial shaft 102 or the like, to a relatively thicker cylindrical block 104. Both the second side plate 80 and the cylindrical block 104 have laterally projecting aligned mounting studs 106 which may actually consist of cylindrical heads on boltlike members threaded into the block 104 and opposed side plate 80. The cylindrical heads or studs 106 are slidably received within a pair of opposed vertically elongated closed end guide slots 108 provided in the opposite side walls of the housing 22 forward of the positioning slots 42. It is through these studs 106 that the entire mounting unit 20 can be vertically adjusted within the housing 22. In order to provide both for the vertical adjustment of the mounting unit 20 and a fixing of the mounting unit 20 in its vertically adjusted position, a vertically elongated threaded adjusting shaft 110 is received through an inwardly projecting mounting ear 112 affixed to the side wall 24 against which the cylindrical block 104 is positioned. This mounting ear 112 is located toward the upper end of the side Wall 24 immediately below the opposed tracks 30 and 32 for the top safety panel 28. The adjusting shaft 110 is provided with an enlarged upwardly projecting gripping head 114 which extends above the top of the housing 22, and a shoulder portion 116 immediately below the manipulating handle or head 114 which bears against the upper surface of the mounting ear 112 through which the shaft 110 projects. An appropriate notch 118 is provided within the inner edge of the safety shield 28 for the reception of the shoulder portion 116 when the shield 28 is moved to its forward closed position. In actual operation, noting FIGURE 1, it will be appreciated that the shaft adjusting head 114 actually provides a convenient handgrip for manipulating the device along the doctor blade 12. The lower portion of the adjusting shaft 110 is threadedly received vertically through an internally threaded bore 120 provided completely through the cylindrical block 104 toward one side of the vertical diameter thereof. In this manner, as the shaft 110 is rotated through a manipulation of the upwardly projecting head or handle 114, the block 104 and consequently the entire mounting unit 20, will vertically rise or lower, guided in the opposed side wall guide slots 108 by the projecting studs 106.

As noted previously, the cylindrical disk 100, which is in turn rigidly aflixed to the adjacent side plate 80, is rotatably adjustable relative to the adjacent block 104. The different rotatably adjustable positions are indicated on the inner peripheral portion of the block 104 by a plurality of spaced guide marks 122 which are selectively aligned with a single guide mark 124 provided on the outer periphery of the disk 100. Each of the guide marks 122 on the block 104 is provided with a corresponding internal lock pin receiving hole or bore 126 within the disk 100 whereby a positive locking of the disk 100, thereby the entire power motor 18, in a rotatably adjusted position relative to the fixed position block 104 can be effected. FIGURE 7 is of interest in illustrating one form of lock pin 128 wherein the projecting end 130 thereof is resiliently biased, by an internal compression spring 132, toward engagement within an aligned bore 126 in the disk 100. The shaft of the lock pin 128 projects beyond the outer face of the block 104 and may slidably bear against the forward edge 136 of the adjacent side wall 24, this forward edge 136 being inwardly offset from the upper portion thereof within which the safety panel track 40 is provided. Finally, an enlarged gripping and manipulating head 138 is provided on the outer end of the lock pin 128 beyond the adjacent side wall 24. Thus, once the particular angle to be ground on the edge 14 of the doctor blade has been determined, the pin 128 is retracted and the actual U-shaped frame which mounts the power motor 18 adjusted, the pin 128 then being released to lock the unit in the desired position. Incidentally, the projecting portion of the lock pin 128 which rides against the forward edge 136 of the adjoining side wall 24 may also act as a means for further stabilizing the mounting unit 20 during the use of the device 10.

In actual practice, the housing 22 will be positioned over the doctor blade 12 through a location of the doctor blade 12 within the blade receiving slots 42. The rear stabilizing arm positioning bar 48 will then be adjusted so as to slidably engage the doctor blade 12 between the leading beveled edge 52 of the bar 48 and the forward edges of the blade receiving slots 42 and both the guide bar 60 and the grinding and stabilizing member 68 which in turn seats on and guides the device 10 along the holder bar 16. The grinding wheel 86, through the vertical and rotational adjustment of the mounting unit 20, is then properly positioned so as to achieve the desired grinding angle, after which the power motor 18 is activated and the device 10 moved along the doctor blade 12 guided on the holder bar 16. In this manner, the edge 14 is perfectly ground at the desired angle and in parallel relation to the holders or shears so as to assure a perfect engagement with the printing rollers. Before the actual grinding operation, it will be appreciated that both safety panels 28 and 38 are properly positioned to protect the operator of the device 10 who, in most instances, will actually grasp the device 10 as illustrated in FIGURE 1.

From the foregoing, it will be recognized that a unique portable doctor blade grinder has been devised, this grinder insuring a perfectly ground edge without the potential danger lack of accuracy, time consumption and expense associated with conventional hand grinding, and without necessitating the use of the large expensive stationary units which require one to actually bring the doctor blade to the unit. The device of the instant invention, both because of its portable nature and its ease of operation, in conjunction with the assured accuracy, enables it to be used directly at the printing machine, and in some circumstances actually in the machine itself. As noted, the parallelism between the blade edge and the blade holders or shears is assured by a guiding of the grinding device directly on the front holder or holder bar.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desiled to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A doctor blade grinding device comprising a powered grinding wheel, housing means, mounting means mounting said grinding wheel in said housing means, and positioning means associated with said housing means for a positioning of said housing means on a doctor blade with the grinding wheel in operative position relative to the blade edge for longitudinal movement therealong, said mounting means including means for vertically adjusting said grinding wheel and means for angularly adjusting said grinding wheel within said housing means, said positioning means including first and second members for receiving a doctor blade therebetween, at least one of said first and second members being selectively adjustable toward the other of said members for a stabilization of the housing means on the involved doctor blade, said housing means including a pair of opposed walls, each defining one of a pair of vertically elongated transversely aligned blade receiving slots extending inwardly through the lower edges of the walls, said positioning means members being mounted on said walls and extending transversely therebetween on opposite sides of the defined slots adjacent the lower ends thereof.

2. The device of claim 1 wherein one of said positioning means members includes an elongated block-like element slidably engageable with a doctor blade holder bar for guided movement of the housing means and grinding wheel along the edge of the involved blade parallel to the holder bar on the blade.

3. The device of claim 2 wherein said mounting means further includes a mounting unit for receiving and mounting the grinding wheel and wheel powering means, said means for vertically adjusting said grinding wheel in cluding opposed vertical guide portions on said opposed walls, a pair of opposed elements on said mounting unit slidably engaged with said guide portions, and means for effecting a vertical movement of said mounting unit and a retention of said mounting unit in a vertically moved position.

4. The device of claim 3 wherein said mounting unit includes clamping means for releasably securing a grinding wheel power means, a block adjacent a first side of said clamping means, said means for angularly adjusting said grinding wheel comprising means rotatably affixing said clamping means to said block, and releasable lock means for selectively locking said clamping means to said block in any of a plurality of rotatably adjusted positions of the clamp means relative to said block.

5. The device of claim 4 wherein one of said pair of opposed elements on said mounting unit is mounted on the side of the block outward from said clamp means, the second of said elements being mounted on the side of said clamp means opposed from said block.

6. The device of claim 5 wherein said means for effecting vertical movement of said mounting unit com prises a vertically elongated threaded shaft, an internally threaded vertical bore in said block, said threaded shaft being threadedly engaged in said bore, and means rotatably fixing said shaft to the side wall adjacent said block whereby rotation of said shaft will effect vertical movement of said block and consequently vertical movement of said mounting unit.

7. A doctor blade grinding device comprising a powered grinding wheel, housing means, mounting means mounting said grinding wheel in said housing means, and positioning means associated with said housing means for a positioning of said housing means on a doctor blade with the grinding wheel in operative position relative to the blade edge for longitudinal movement therealong, said positioning means including first and second members for receiving a doctor blade therebetween, at least one of said first and second members being selectively adjustable toward the other of said members for a stabilization of the housing means on the involved doctor blade, said housing means including a pair of opposed Walls, each defining one of a pair of vertically elongated transversely aligned blade receiving slots extending inwardly through the lower edges of the walls, said positioning means members being mounted on said walls and extending transversely therebetween on opposite sides of the defined slots adjacent the lower ends thereof.

8. The device of claim 7 wherein one of said positioning means members includes an elongated block-like element slidably engageable with a doctor blade holder bar for guided movement of the housing means and grinding wheel along the edge of the involved blade parallel to the holder bar on the blade.

9. The device of claim 1 wherein said mounting means further includes a mounting unit for receiving and mounting the grinding wheel and wheel powering means, said means for vertically adjusting said grinding wheel including opposed vertical guide portions on said opposed walls, a pair of opposed elements on said mounting unit slidably engaged with said guide portions, and means for effecting a vertical movement of said mounting unit and a retention of said mounting unit in a vertically moved position.

10. For use in grinding the edge of an elongated blade having an edge paralleling holder bar afiixed thereto, a

portable grinding device, said device comprising a grinding element mount, blade receiving means for mounted engagement with a blade to be ground, means aflixing said grinding element mount on said blade receiving means for grinding engagement of a grinding element with a blade edge, and guide means on said blade receiving means for sliding engagement longitudinally along a blade associated holder bar whereby a sliding of a mounted grinding element along a blade edge parallel to the associated holder bar can be efiected, said blade receiving means including a pair of opposed wall portions each defining one of a pair of transversely aligned elongated blade re ceiving slots, said grinding element mount being received transversely between said wall portions to one side of said slots, said guide means being afiixed to said opposed wall portions and extending transversely therebetween to the same side of said slots as said grinding element mount, said guide means being positioned below said grinding element mount and presenting a guiding edge portion inwardlu directed toward the plane of said slots.

11. [For use in grinding the edge of an elongated blade having an edge paralleling holder bar affixed thereto, a portable grinding device, said device comprising a grinding element mount, blade receiving means for mounted engagement with a blade to be ground, means afiixing said grinding element mount on said blade receiving means for grinding engagement of a grinding element with a blade edge, and guide means on said blade receiving means for sliding engagement longitudinally along a blade associated holder bar whereby a sliding of a mounted grinding element along a blade edge parallel to the associated holder bar can be effected, said blade receiving means including a pair of opposed Wall portions defining a pair of transversely aligned elongated blade receiving openings, said grinding element mount being received transversely between said wall portions generally to one side of said openings, said guide means being affixed to said opposed wall portions and extending therebetween generally to the side of said openings, said guide means being positioned below said grinding element mount and presenting a guiding edge portion inwardly directed relative to said openings.

12. The device of claim 11 wherein said grinding element mount includes a mounting unit for receiving and mounting a grinding wheel and wheel powering means, and adjusting means for vertically adjusting the grinding wheel, said adjusting means including opposed vertical guide portions on said opposed wall portions, a pair of opposed elements on said mounting unit slidably engaged with said guide portions, and means for effecting a vertical movement of said mounting unit and retention of said mounting unit in a vertically moved position.

13. The device of claim 11 wherein said guide means includes an elongated block-like element slidably engageable along a blade associated holder bar.

14. The device of claim 11 including means for angularly adjusting the mounting unit which receives and mounts the grinding wheel and wheel powering means.

15. The device of claim 14 wherein said mounting unit includes clamping means for releasably securing a grinding wheel power means, a block adjacent a first side of said clamping means, said means for angularly adjusting said mounting unit comprising means rotatably afiixing said clamping means to said block, and releasable lock means for selectively locking said clamping means to said block in any of a plurality of rotatably adjusted positions of the clamp means relative to said block.

References Cited UNITED STATES PATENTS 1,863,036 6/1932 Wicke 51-173 1,961,328 6/1934 Beach 51-173 X 1,834,972 12/ 1931 Satterstrom 51-249 X 2,792,036 5/ 1957 Buttke 51-2 9 FOREIGN PATENTS 351,-617 4/ 1922 Germany.

JAMES L. JONES, 111., Primary Examiner U.S. Cl. X.R. 51-173 

